Biomedical subjects

T O Bennett

Publications and source records attributed to T O Bennett.

13 recordsLinked to original sources

PubMed1978

Intracameral phosphate buffer in alkali burns.

We perfused the eyes of albino rabbits with a phosphate buffer to see if the damage to cornea and lens produced by alkali might be reduced. The rabbits were divided into five groups: in the first (control) group undamaged eyes were perfused; in the other four the corneas were burned with sodium hydroxide. The second group was not treated; the remaining three were treated with buffer at once, after fifteen minutes and after thirty minutes. Our results showed that provided this regime is used within thirty minutes of exposure, the effects of the insult are reduced.

Animals↗

PubMed1977

Ocular manifestations of toxic epidermal necrolysis associated with allopurinol use.

A 54-year-old man was receiving allopurinol therapy to treat hyperuricemia that followed an inferior wall, myocardial infarction. After three weeks of allopurinol therapy, the patient developed signs and symptoms of toxic epidermal necrolysis that included pseudomembranous conjunctivitis with ulcerative lesions on the lids and conjunctiva, and punctate corneal staining with subsequent corneal abrasions. Treatment with topical antibiotics and artificial tears relieved the symptoms somewhat, but punctate staining and dry eyes persisted after 14 months of follow-up. Bilateral corneal ulcers developed and necessitated conjunctival flaps in each eye. Visual acuity in each eye was 20/40.

Allopurinol↗

PubMed1977

Histocompatibility matching in poor prognosis combined procedure keratoplasty.

To determine the effect of histocompatibility matching and mismatching at the rabbit leukocyte-locus A (RL-A locus) on graft survival in rabbits, we created a model to enhance graft failure. Rabbit corneas received alkali burns with consequent vascularization of the graft bed. Each rabbit underwent large (10-mm) penetrating keratoplasty and simultaneous lens extraction. Grafts in four of six corneas from the matched group remained transparent for the extent of the experiment; none of the grafts in the mismatched group were transparent at the end of the experiment.

Animals↗

PubMed1975

Octafluorocyclobutane in vitreous and aqueous humor replacement.

Vitreous replacement with air, pure octafluorocyclobutane (C4F8), and mixtures of 40% C4F8 and 60% air was done in owl monkeys to determine ocular toxicity and duration of gas within the vitreous compartment. Large volumes of gas mixture and pure C4F8 caused posterior subcapsular cataract formation. Pure C4F8 expands in the vitreous within 24 to 48 hours. A 1.0-ml mixture of 40% C4F8 and 60% air lasted 12.7 days and did not cause ocular changes. However, anterior chamber aqueous replacement with pure C4F8 or gas mixture resulted in cataract production. Twenty-four and fourty-eight hours after injection of 0.1-ml pure C4F8 in the vitreous of experimental rabbits, presence of oxygen, nitrogen, and carbon dioxide was shown by gas chromatographic analysis. This finding supports the hypothesis of volume expansion secondary to diffusion of above-mentioned gases inside the C4F8 gas bubble.

Absorption↗

PubMed1975

Histocompatibility matching in poor-prognosis penetrating keratoplasty.

Rabbits were haplotyped for the major rabbit leukocyte-locus A (RL-A locus), which is analogous to the human leukocyte-locus A (HL-A locus). The rabbits were divided into five groups, and the groups were arranged to provide a controlled experimental setting. Standardized alkali burns were induced in selected groups to produce heavy vascularization of the corneal bed. Groups with completely histocompatible corneal donors for the RL-A locus had a 9 out of 10 success rate when keratoplasty was performed on a vascularized bed. Another group of rabbits mismatched at the RL-A locus with histoincompatible corneal donors were prepared in the same manner and had a success rate of 1 out 9. A probable significant difference (P less than 0.005) using Fischer's exact test was found between the two groups.

Animals↗

PubMed1975

Effects of intravitreal prostaglandins on retinal vasculature.

One dose of each prostaglandin preparation was injected into the vitreous body of the right eye of 64 rabbits. Doses less than 200mug caused no toxicity. Doses greater than 200mug exhibited the following changes observed by ophthalmoscopic observation, fluorescein angiography, histologic preparation, and electron microscopy: vascular leakage, vascular occlusion, hemorrhage, and retinal detachment. Electron micrographs revealed damaged retinal vascular endothelial cells. These changes were considered secondary toxic phenomena and did not occur at physiologic prostaglandin concentrations.

Animals↗

PubMed1975

Intravitreal injection of autologous blood in primates.

Thirteen owl monkeys received intravitreal injections of 0.3 ml of autologous blood in single or multiple injections. Blood was antiocoagulated either with heparin to inhabit clot formation or with citrate to allow clot production within the vitreous body. Clinical observations showed that approximately 60% of the heparinized eyes cleared, whereas only about 5% of the citrated eyes did. Thus, clotting appears to have a significant effect on the clearance of blood from the vitreous chamber. In addition to the abscence of hemosiderosis, histological and ultrastructural studies of retinas showed no retinal damage.

Animals↗

PubMed1975

Postoperative endophthalmitis: a comparison of methods for treatment and prophlaxis with gentamicin.

Toxicity of gentamicin and its use in the treatment of experimentally induced Pseudomonas aeruginosa endophthalmitis were studied in the postoperative aphakic eye. The retinal toxicity of intravitreal gentamicin was different from toxicity in the intact eye and varied with the method of injection. Successful prophylaxis of induced postoperative infection was obtained with an intravitreal injection of 30 mu-g of gentamicin but not with sub-Tenon's administration of gentamicin. Treatment for progressive endophthalmitis was effective with high dose (200 mu-g) gentamicin alone, or a combination of low-dose (30 mu-g) gentamicin with topical and systemic gentamicin. Either sub-conjunctival and systemic gentamicin or low-dose gentamicin alone was ineffective once endophthalmitis was in progress. Although vitrectomy removed abscess products, it failed in this experiment to provide better results than the other modes of therapy.

Animals↗

PubMed1974